The present invention relates to a cabinet for electrostatic painting, which comprises a framework which supports flat walls, whose inner surfaces bound a volume inside which at least one pneumatic distributor is installed, which distributes the powders to be applied onto the workpiece to be painted, also contained inside said volume.
In the field of the electrostatic painting, the painting cabinets essentially perform two functions. The first function is of preventing the organic powders, which are delivered by the pneumatic distributor(s) and do not fulfil their task of forming the desired coating on the workpiece, from propagating throughout the surrounding environment.
The second function is of making it possible said powders to be at least partially recovered, with undoubted economical advantages and of environmental protection. In this regard, the rate of proper application of the powders delivered by the pneumatic distributor onto the surfaces of the workpiece is estimated to be of 30% on the average. In the field of electrostatic painting by means of powders, contrarily to what happens in case of painting by means of solvent-based paints, each time that the colour of the coating powder is changed, any traces of the preceding powder, and namely, not only those powder residues which are contained inside the pneumatic distributor and in the relevant equipment, but also those which settle on all of the interior surfaces of the walls of the cabinet, have to be removed.
In fact, the risk exists that the previously used powder, only provisorily sticking to the inner surfaces of the walls of the cabinet, gets detached from said surfaces going to form the coating on the workpiece together with the powder which is being presently delivered by the distributor, thus altering the end colour of said workpiece.
In the cabinets known from the prior art, the cleaning of the inner surfaces is carried out by means of a manual procedure at each colour change.
Both the uncomfort and the costs deriving from such an operation need not be explained.
A more technologically advanced type of cabinets have such a structure as to make it possible for the walls of the same cabinet to be easily replaced. Such walls are made from sheets of plastic materials, to be disposed of after use.
Also such a kind of solution is not free from drawbacks, such as, e.g., the need of having to materially purchase and install the plastic sheets to be used, and of disposing of the used sheets. The handling of the used sheets requires special precautions, dictated by the toxicity of the substances which coat them.